Compression couplings consist of three components- nut, ring and seat. A coupling is used to connect a tubing system, which can be a pipe and fixture or two pipes. Compression fittings come in a variety of designs, but the functioning is similar. What happens is that a compression coupling exerts a clamping force on the fitting, which acts a seal. The compression ring is slid onto a tube while the nut follows behind it, then the protruding part of the pipe goes into the seat, and it is screwed on. As the nut tightens, it applies a downward force on the compression ring, which in turn, forms a leak-free seal. Compressions fitting are designed for a number of applications, and it helps to know which ones work where before buying.

Plumbing Applications

The plumbing system is the biggest user of compression fittings. Instead of soldering copper pipes together, most installers use coupling for connections. The advantage of having these fittings on plumbing is that a homeowner can easily replace them because they don’t require any skills for the tasks. When you need to take a system apart, for example, when renovating a bathroom, the fittings are just as simple to undo. It is possible for a compression coupling to develop a leak over time and when that happens, you can loosen the nut and tighten it again. Note that compression fittings are not just for copper pipes; you can have them in plastic and steel as well. You just have to get the coupling of the same material, which is easy enough what with the diversity of products.

Compression fittings can be used in both water and gas installations. Fittings are available in different shapes and sizes, so they cater to a range of plumbing fixtures from toilets to faucets. When an installation has an elbow, instead of trying to bend the tubing, it’s possible to get a coupling that corresponds to that particular angle. In instances where a system requires more than two lines, a multi-port coupling comes in handy. Such connections provide additional outlets whether in water or gas supply systems.

Connecting Appliances

Another application where compression fittings come in is when linking devices to the plumbing. Machines that require water or gas supply such as washers need couplings to secure the connection. An icemaker is also connected to a refrigerator using a compression fitting.

Proper Use of Couplings

It is advisable to utilise fitting in stationary installations. The primary objective of a coupling is to prevent the pipe from disconnecting from the tubing. One downside of a compression fitting is that you cannot prevent installation from turning when there is movement, and that can cause a leakage. For instance, when you move a fridge that is connected to an icemaker with a coupling, stress is exerted, causing the fitting to rotate and leak. Such a leakage is hard to notice, which is why you may only realise after seeing a pool of water at the bottom of the fridge. Compression fittings should also receive adequate lubrication before installation to ensure a tight seal.

Fittings used on plastic pipes should not be tightened too much such that you cut off the supply or break the piping. Tighten the nut until there is resistance and then proceed slowly to ensure there is no leaking. It may take a while to know the best way to tighten a compression fitting. Couplings are an ideal choice when dealing with space constraints like under a kitchen sink. To get the most out of compression couplings, avoid reusing old ones. It may be possible to reuse a nut but not the compression ring because the only way it can be removed from the tubing is to cut it. Visit for more details.